Electrochemically controlled solid phase microextraction based on a conductive polyaniline‐graphene oxide nanocomposite for extraction of tetracyclines in milk and water

Abstract

BACKGROUND Tetracycline antibiotics are employed for human and animal health and for speeding up growth rates. However, their presence in food products and environmental waters has been a concern for some years. Therefore, a variety of sample preparation methods have been developed for the analysis of tetracycline residues in these matrices. RESULTS An electrochemically controlled solid phase microextraction based on a modified copper electrode with polyaniline/graphene oxide (PANI/GO) conductive nanocomposite was developed for the extraction of oxytetracycline, tetracycline and doxycycline before high‐performance liquid chromatography‐UV analysis. PANI/GO was synthesized by in situ chemical oxidative polymerization, characterized by scanning electron microscopy and Fourier‐transform infrared spectroscopy, and bound on the electrode using high purity conductive double‐sided adhesive carbon glue. The significant factors affecting the performance of microextraction were investigated and optimized. Under the optimized conditions [sample, 15 mL; sorbent, 10 mg; pH, 3.0; electroextraction voltage, −0.9 V; electroextraction time, 20 min; eluent (MeOH/NH3), 500 μL; and desorption time, 5 min], the limits of detection for target analytes were in the ranges 0.32–1.01 and 2.42–7.59 μg L−1 in water and milk samples, respectively. The linear ranges were 1.06–750 μg L−1 for water and 8.05–750 μg L−1 for milk samples. The intra‐day and inter‐day precisions were 2.32–3.80 and 3.29–4.25, respectively. The method was applied to the determination of analytes in milk and water samples with different fat contents, and the recoveries were obtained in the range 71–104%. CONCLUSION The developed electro‐microextraction method provides a facile, rapid, cost‐effective, sensitive and efficient promising procedure for the extraction of antibiotics in complex matrices. © 2020 Society of Chemical Industry

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“…This method allows determining the concentration of tetracycline in the range from 0.001 to 10 ng/mL. H. Sereshti et al developed a method that makes it possible to determine target analytes within the detection limits of 0.32-1.01 and 2.42-7.59 μg/L in water and milk samples, respectively [21]. In the study [22], a method was proposed to obtain organometallic frameworks for dispersive solid-phase extraction to determine tetracycline traces in honey.…”

Growth ZIF-8 on carbon cloth for electric field enhanced thin film microextraction of tetracyclines in milk and honey

“…The recoveries increased with the increase of pH at 4.0-6.0, while at pH 7.0-9.0, the recoveries decreased. This may be due to the instability of ZIF-8 under acidic conditions, and TCs were easily dissolved in water and degraded into other substances under alkaline conditions, and both TCs and ZIF-8 were negatively charged and repel each other (Sereshti et al 2021). Therefore, pH 6.0 was chosen as the best value.…”

Natural thymol‐based ternary deep eutectic solvents: Application in air‐bubble assisted‐dispersive liquid‐liquid microextraction for the analysis of tetracyclines in water

“…However, the maximum residue limits of antibiotics in water have not been determined yet due to inadequate data [4]. In recent years, a variety of sample preparation methods followed by liquid chromatography such as SPE [5][6][7][8][9][10], SPME [11,12], LLME [13], dispersive LLME (DLLME) [14,15], and tandem methods like ultrasound-assisted matrix/SPME [16], magnetic SPE/DLLME [17], MSPE/LLE [18], and salt-induced homogenous LLE/DLLME [19] have been reported for the analysis of TCs in different matrices. Farajzadeh et al in 2012 developed a disperser-free version of DLLME named air assisted-or air-agitated LLME (AA-LLME) method in which the extraction solvent is dispersed into the aqueous phase as fine droplets by sucking and injecting the mixture of aqueous sample solution and extraction solvent with a syringe for several times in a conical test tube [20].…”

“…However, the maximum residue limits of antibiotics in water have not been determined yet due to inadequate data [4]. In recent years, a variety of sample preparation methods followed by liquid chromatography such as SPE [5–10], SPME [11,12], LLME [13], dispersive LLME (DLLME) [14,15], and tandem methods like ultrasound‐assisted matrix/SPME [16], magnetic SPE/DLLME [17], MSPE/LLE [18], and salt‐induced homogenous LLE/DLLME [19] have been reported for the analysis of TCs in different matrices.…”